1. Field of the Invention
The present invention relates to a recording apparatus including a colorimeter.
2. Description of the Related Art
Inkjet printers are one of recording apparatuses, and some inkjet printers are provided with a colorimetric function. Such an inkjet printer performs colorimetric measurement on a recorded color image for color calibration or the like. Further, based on the colorimetric data, the printer reflects the result in next image recording and obtains desired color reproduction.
Generally, color data is expressed as color patches of each color arranged in grid-like manner. In the general colorimetric measurement process, the recorded color patches are dried, the colorimetric sensor moves in the recording medium width direction to perform colorimetric measurement on the rows of the color patches are subjected to one by one, and then the measured recording medium is discharged.
In the process, one of the most important points is to accurately stop the unit patch at a colorimetric position of the colorimeter. This is because the measurement at an unexpected position is a main factor in causing colorimetric errors.
In the known techniques, the color patches are not always stopped at an expected position due to errors such as slips in the conveyance system, and as a result, in many cases, the colorimetric measurement is not appropriately performed.
In Japanese Patent Application Laid-Open No. 2008-290268, first, a feed amount determination patch is recorded on a recording medium. Then, colorimetric measurement is performed on the feed amount determination patch to calculate an error when the feed amount determination patch is conveyed by a set feed amount for conveying to a colorimetric position. In a main measurement, the set feed amount corrected by the calculated error as a correction value is used.
In the technique discussed in Japanese Patent Application Laid-Open No. 2008-290268, the correction value is calculated for each paper type. Consequently, conveyance errors due to an environment and the paper type can be corrected. However, in reality, if the recording media of the same type are used, conveyance errors are generated depending on differences in diameters of rolls (curl amounts), chart lengths, print Duties, and the like, and displacement may be caused at the time of pressing.
In addition, in a case where a patch group is long in the conveyance direction or switching between forward feed and back feed occurs due to a layout of a plurality of patches, conveyance errors may be accumulated and hinder accurate conveyance of a color patch for colorimetric measurement to the reading position. In such a case, there is a possibility that reading of the color patch arrays is skipped, and appropriate colorimetric measurement may not be performed. To prevent such an issue, the size of the patch may be increased in the conveyance direction. However, this causes increase in the usage of paper and decrease in the throughput due to the increase in the conveyance distance.